Process for developing dyeings and prints produced with the tetrasulfuric acid leuco-ester of tetrahydro-1:2:2&#39;:1&#39;-dianthraquinoneazine



Patented May 15, 1951 UNITED STATES PATENT OFFICE Jacques Duport and Richard Spennrath, Basel, Switzerland, assignors to. Durand & Huguenin A. G., Basel, Switzerland, 2. Swiss firm No Drawing. Application May 31, 1950, Serial N 0. 165,364. In Switzerland May 13, 1948 10 Claims.

The present invention is a continuation-inpart application to our co-pending patent application Ser. No. 92,258 filed on May 9, 1949, now abandoned.

Vat dyestuffs are easily regenerated from salts of sulphuric acid leuco-ester vat dyestuffs (Indigosols) by acid oxidation, if desired, with the addition of a catalyst.

However, the behaviour of the ester salts with respect to avid oxidising agents varies. Thus, while one product can be developed by mild oxidation, another product may require stronger oxidising conditions for development. The oxidation potential required for the development of a dyeing of an ester salt therefore varies considerably with different ester salts.

It is also known that certain vat dyestuffs which are produced by the oxidation of their ester salts on the fibre are easily oxidised by the oxidising agent used for developing the dyeing, and this causes a change in the tint of the dyeing. Even when it is possible to calculate accurately the quantity of the agent splitting off oxygen which is required to develop a particular ester salt at a given temperature in a given time, it frequently happens that very small changes in the conditions, which can never be entirely avoided in practice, suffice to cause the over-oxidation of sensitive ester salt dyeings.

U. S. Patent No. 1,779,365 describes the use of oxidisable compounds having a buffer action such, for example, as aromatic amino-sulphonic acids, which enable dyeings with salts of sulphuric acid leuco-esters of vat dyestuffs to be developed normally by acid oxidation in steam development processes. The compounds used must be more easily oxidisable than the vat dyestuff, in order that the compound may take up the excess of oxidising agent present and protect the dyeing which has already developed against over-oxidation. However, this process is not satisfactory in the case of the tetrasulphuric acid ester of tetrahydro-l 2 :2 l'-dianthraquinoneazine, because over-oxidation can occur notwithstanding the use of a large quantity of the buffering compound.

In U. S. Patent No. 2,224,280 is described a process for dyeing or printing with salts of tetra-sulphuric acid leuco-esters of vat dyestuffs of the tetrahydro-l :212 1-dianthraquin oneazine group by acid oxidation in a steam development process, in which ammonium nitrate is added to the dyebath or printing paste in addition to sodium chlorate. This process is indeed an improvement on the process of U. S. Patent No. 1,779,305, but it has been found in practice that unreliable development in the case of certain ester salts has to be reckoned with. Almost every batch of the salt of sulphuric acid ester of tetrahydro 1:2:2' :1 dianthraquinoneazine produced requires in dyeing or printing a readjustment of the relative proportions of sodium chlorate and ammonium nitrate.

.Finally, U. S. Patent No. 2,234,301 describes a process for dyeing or printing textile fibres with leuco-ester salts ofvat dyestuffs by acid oxidation in the presence of protective substances, in which there are used as protective substances. hydroxy-compounds which when oxidised are easily converted into quinones or quinone-like compounds. Development. is brought about by the wet method (the so-called nitrite method). However, the use of these hydroxy compounds in steam development processes using the tetrasulphuric acid ester of tetrahydro-l:2:2':l'-dianthraquinoneazine leads to variable resultswhich are unsatisfactory in practice.

The present invention is based on the observation that satisfactorily developed dyeings and prints with the tetrasulphuric acid ester of tetrahydro-1:2:2:1-dianthraquinoneazine can be obtained by acid oxidation in steam development processes in the presence of at least one buffer substance, when there is used as the buiTer substance a sulphonic acid or carboxylic acid of a mono-hydroxynaphthalene or a water-soluble salt of such an acid. When such a compound or a, mixture of such compounds is added directly to the dyestuff or to the printing colour or dyebath it becomes possible to vary within certain limits in the printing colour or the dyebath the proportions of the substances necessary for development without any change in shade of the developed print or dyeing. Such prints are hardly sensitive to variations in the steaming conditions and the requirements which practical considerations .demand in any particular case are entirely satisfactory.

As especially suitable sulphonic acid or carboxylic acids of mono-hydroxynaphthalenes there Example 1 A printing paste of the following composition is prepared:

Parts The tetrasulphuric acid ester of the leucocompound of tetrahydro-l :2 2' :1 -dianthraquinoneazine 21% powder 9 2-naphthol-8-sulphonic acid 2 Water 18 Neutral thickening 60 Ammonium thiocyanate 1:1. 8 Sodium chlorate 1:3 2 Sodium vanadate 1% 1 The material is printed with the above printing paste, dried, steamed for 8 minutes in the Mather-Platt apparatus, rinsed, soaped for minutes at the boil, rinsed and dried.

A handsome clear bright blue print is obtained.

Example 2 A printing paste of the following composition is prepared:

Parts A mixture of the tetrasulphuric acid ester of the leuco-compound of tetrahydro- 1:2:2':1-dianthraquinoneazine 21% powder and 1-naphtho1-4-sulphonic acid in the ratio 9:2 11 Water 1 18 Neutral starch-tragacanth thickening 60 Ammonium thiocyanate 1:1 8 Sodium chlorate 1:3 2 Ammonium vanadate 1% 1 A material is printed with the above printing paste, dried, steamed for 8 minutes in the Mather- Platt apparatus, rinsed, soaped for 5 minutes at the boil, rinsed and dried.

A handsome clear bright blue print Example 3 90 parts of the tetrasulphuric acid ester of tetrahydro-l 2 2' 1,dianthraquinoneazine containing 21% of vat dyestuif are mixed with 25 parts of the sodium salt of l-naphthol-S-sulphonic acid.

The resultant dyestuff preparation is used for the production of a printing paste suitable in steam development processes for instance according to the following recipe:

is obtained.

Parts Dyestufi preparation 11.5 Water 17.5 Neutral starch-tragacanth thickening---" 6O Ammonium thiocyanate 1:1 8 Sodium chlorate 1:8 2 Ammonium vanadate 1% 1 A material is printed with the above printing paste, dried, steamed for 8 minutes in the 4 Mather-Flatt apparatus, rinsed, soaped 'for 5 minutes at the boil, rinsed and dried. A handsome clear vivid blue print is thus produced.

Example 4 A printing paste of the following composition is prepared:

' Parts The tetrasulphuric acid ester of the leucocompound of tetrahydro-l :2 :2 :1-dianthraquinoneazine 21% powder 9 l-naphtholl-sulphonic acid 2 Water 18 Neutral starch-tragacanth thickening 60 Ammonium thiocyanate 1:1 8 Sodium chlorate 1:3 2 Ammonium vanadate 1 A material is printed with the above printing paste, dried, steamed for 8 minutes in the Mather- Platt apparatus, rinsed,.soaped for 5 minutes at the boil, rinsed and dried. A handsome clear bright blue print is obtained.

Example 5 A printing paste of thefollowin composition is prepared:

Parts The tetrasulphuric acid ester of the leucocompound of tetrahydro-l :2 :2 :1-dianthraquinoneazine 21% powder 9 1-naphthol-3-sulphonic acid 2 Water 18 Neutral thickening 60 Ammonium thiocyanate 1:1 8 Sodium chlorate 1:3 2 Ammonium vanadate 1% 1 A material is printed with the above paste, dried, steamed for 8 minutes in the Mather-Platt apparatus, rinsed, soaped for 5 minutes at the boil, rinsed and dried. v

A handsome clear bright blue print is obtained.

Example 6 parts of tetrasulphuric acid ester of tetrahydro-l 2 :2 1 -dianthraquinoneazine containing 21% of vat dyestufi are mixed with 25 parts of a mixture consisting of equal parts of the sodium salt of 1-naphthol-4-sulphonic acid and of the sodium salt of 1-naphtho1-8-sulphonic acid.

, The resultant dyestufi preparation is used for the production of a printing paste suitable in steam development processes for instance according to the following recipe:

Parts Dyestuff preparation 11.5 Water 17.5 Neutral starch-tragacanth thickening 6O Ammonium thiocyanate 1:1 8 Sodium chlorate 1:3 2 Ammonium vanadate 1% 1 A material is printed with the above printing paste, dried, steamed for 8 minutes in the Mather- Platt apparatus, rinsed, soaped for 5 minutes at the boil, rinsed and dried. A handsome clear vivid blue print is thus produced.

Example 7 A printing paste of the following composition is prepared:

' Parts The tetrasulphuric acid ester of the leucocompound of tetrahydro-l :2 2' l -dian- A printing paste of the following composition is prepared:

Parts The tetrasulphuric acid ester of the leucocompound of tetrahydro-l :2 2 1'-dianthraquinoneazine 21% powder 9 Sodium-l-naphtholl-sulphonate 2.5 Water 17.5 Neutral thickening 60 Ammonium thiocyanate 1:1 8 Sodium chlorate 1:3 2 Ammonium vanadate 1% 1 A material is printed with the above paste, dried, steamed for 8 minutes in the Mather-Platt apparatus, rinsed, soaped for 5 minutes at the boil, rinsed and dried.

A handsome clear bright blue print is obtained.

What we claim is:

1. A process for producing dyeings and prints with the tetrasulphuric acid ester of tetrahydro- 1 :2 :2 l-dianthraquinoneazine, which comprises developing the said leuco-ester on the material by a steam developing process with a chlorate as oxidizing agent in the presence of at least one buffer substance selected from the group consisting of 1-naphthol-3-sulphonic acid, l-naphthol- 4-sulphonic acid, l-naphthol-S-sulphonic acid, 1-naphthol-8-sulphonic acid, 2-naphthol-8-sulphonic acid, 2-naphthol-6-carboxylic acid and water-soluble salts of the said acids.

2. A process for producing prints with the tetrasulphuric acid ester of tetrahydro-1:2:2':1'- dianthraquinoneazine, which comprises printing on the material a printing colour containing the said leuco-ester, a thickening agent, a chlorate as oxidizing agent, a substance capable of liberating acid when heated, and at least one buffer substance selected from the group consisting of 1-naphthol-3-sulphonic acid, 1-naphthol-4-sulphonic acid, 1-naphthol-5-sulphonic acid, 2- naphthol-8-sulphonic acid, 1-naphthol-8-sulphonic acid, 2-naphthol-6-carboxylic acid and water-soluble salts of the said acids.

3. A process as claimed in claim 2, wherein the oxidizing agent is sodium chlorate.

4. A process as claimed in claim 2, wherein the substance capable of liberating acid when heated is ammonium thiocyanate.

5. A process as claimed in claim 2, wherein the printing colour also contains a catalyst.

6. A process as claimed in claim 5, wherein the catalyst is ammonium vanadate.

'7. A process for producing prints with the tetrasulphuric acid ester of tetrahydro-lz2z2'z1' dianthraquinoneazine, which comprises printing on the material a printing colour containing the said leuco-ester, a neutral thickening, sodium chlorate as oxidizing agent, ammonium thiocyanate as a substance capable of liberating acid when heated, ammonium vanadate as a catalyst, and sodium l-naphthoL-sulphonate as a buffer substance, and developing the print by subjecting it to steaming.

8. A process for producing prints with the tetrasulphuric acid ester of tetrahydro1:2:2:1- dianthraquinoneazine, which comprises printing on the material a printing colour containing the said leuco-ester, a neutral thickening, sodium chlorate as oxidizing agent, ammonium thiocyanate as a substance capable of liberating acid when heated, ammonium vanadate as a catalyst, and l-naphthol-4-sulphonic acid as a bufier substance and developing the print by subjecting it to steaming.

9. A process for producing prints with the tetrasulphuric acid ester of tetrahydro-1:2:2:1'- dianthraquinoneazine, which comprises printing on the material a printing colour containing the said leuco-ester, a neutral thickening, sodium chlorate as oxidizing agent, ammonium thiocyanate as a substance capable of liberating acid when heated, ammonium vanadate as a catalyst, and sodium-1-naphtho1-8-sulphonate as a bufier substance, and developing the print by subjecting it to steaming.

10. A process for producing prints with the tetrasulphuric acid ester of tetrahydro-1:2:2':1- dianthraquinoneazine, which comprises printing on the material a printing colour containing the said leuco-ester, a neutral thickening sodium chlorate as oxidizing agent, ammonium thiocyanate as a substance capable of liberating acid when heated, ammonium vanadate as a catalyst, and a mixture of sodium-l-naphthol-l-sulphonate and of sodium-1-naphth01-8-su1phonate as a bufier substance, and developing the print by subjecting it to steaming.

JACQUES DUPORT. RICHARD SPENNRATH.

No references cited. 

1. A PROCESS FOR PRODUCING DYEINGS AND PRINTS WITH THE TETRASULPHURIC ACID ESTER OF TETRAHYDRO1:2:2'':1''-DIANTHRAQUINONEAZINE, WHICH COMPRISES DEVELOPING THE SAID LEUCO-ESTER ON THE MATERIAL BY A STEAM DEVELOPING PROCESS WITH A CHLORATE AS OXIDIZING AGENT IN THE PRESENCE OF AT LEAST ONE BUFFER SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF 1-NAPHTHOL-3-SULPHOJIC ACID, 1-NAPHTHOL4-SULPHONIC ACID, 1-NAPHTHOL-5-SULPHONIC ACID, 1-NAPHTHOL-8-SULPHONIC ACID, 2-NAPHTHOL-8-SULPHONIC ACID, 2-NAPHTHOL-6-CARBOXYLIC ACID AND WATER-SOLUBLE SALTS OF THE SAID ACIDS. 